This invention relates to a very late antigen (VLA) protein family isolated from human cell tissue which has extracellular matrix adhesion function.
Human very late antigen (VLA) heterodimers VLA-1 and VLA-2 have been disclosed by Hemler et al (J. Immunol. 131:334, 1983; J. Immunol. 132:3011, 1984; Eur. J. Immunol. 15: 502, 1985; J. Biol. Chem. 260:15246, 1985; J. Clin. Invest. 78:696, 1986). These are separate protein complexes of M.sub.r 210,000/130,000 and M.sub.r 165,000/130,000, respectively, which share a common .beta. subunit of M.sub.r 130,000, but have unique .alpha. subunits. Both VLA-1 and VLA-2 appear very late after T cell activation and varying amounts of VLA-1 relative to VLA-2 are obtained during long term T cell culture. A monoclonal antibody for VIA-1, from murine hybridoma TS2/7, is sold by T Cell Sciences, Inc. for identification of long term or chronically activated T lymphocytes and thymocytes, and assessment of human T-cell function, particularly in response to antigenic and mitogenic stimuli. Detection of VLA-1 is also used for correlation and assessment of chronic autoimmune diseases, such as multiple sclerosis, systemic lupus erythematous, and rheumatoid arthritis, as well as chronic viral infections. For example, increases in VLA-1 expression have been observed on the surface of T-cells of active multiple sclerosis patients.